small improvement on error reporting

annotation/src/main/java/lcsb/mapviewer/annotation/cache/BigFileCache.java

@@ -747,7 +747,7 @@ public class BigFileCache {
 			if (e.getCause() instanceof URISyntaxException) {
 				throw (URISyntaxException) e.getCause();
 			} else if (e.getCause() instanceof IOException) {
-				throw (IOException) e.getCause();
+				throw new IOException((IOException) e.getCause());
 			} else {
 				throw new InvalidStateException(e);
 			}

annotation/src/main/java/lcsb/mapviewer/annotation/services/genome/AbstractReferenceGenomeConnector.java

@@ -383,9 +383,9 @@ public abstract class AbstractReferenceGenomeConnector extends CachableInterface
 			if (e.getCause() instanceof URISyntaxException) {
 				throw (URISyntaxException) e.getCause();
 			} else if (e.getCause() instanceof IOException) {
-				throw (IOException) e.getCause();
+				throw new IOException((IOException) e.getCause());
 			} else if (e.getCause() instanceof ReferenceGenomeConnectorException) {
-				throw (ReferenceGenomeConnectorException) e.getCause();
+				throw new ReferenceGenomeConnectorException((ReferenceGenomeConnectorException) e.getCause());
 			} else {
 				throw new InvalidStateException(e);
 			}

annotation/src/main/java/lcsb/mapviewer/annotation/services/genome/ReferenceGenomeConnectorException.java

@@ -37,4 +37,8 @@ public class ReferenceGenomeConnectorException extends Exception {
 		super(message);
 	}
 
+	public ReferenceGenomeConnectorException(Exception cause) {
+		super(cause);
+	}
+
 }